Background and Objectives: Postoperative pain and stress elicit
hormonal changes. We aimed at comparing the effects of wound
infiltration with ketamine versus dexmedetomidine on postoperative
pain and stress response.
Methods: This double-blinded study included ninety patients scheduled
for total abdominal hysterectomy and were randomly assigned into
three groups to receive local wound infiltration with 40 mL of 0.25%
bupivacaine (group C), plus 2 mg/kg ketamine (group K) or 2 lg/kg
dexmedetomidine (group D). Primary outcome was postoperative
morphine consumption; secondary outcomes included first request of
analgesia, VAS scores at rest and movement (VAS–R/M) and side effects.
Serum cortisol, prolactin and glucose levels at baseline, pre-infiltration,
6 and 24 h postoperatively were measured.
Results: Rescue analgesia was less in K (6.80
3.19 mg) and D
(8.39
3.86 mg) compared to C (13.33
4.01 mg) (p < 0.05). First
request of analgesia was delayed in K (7.60
4.16 h) and D
(6.00
3.73 h) compared to C (4.20
1.13 h) (p < 0.05). Both VAS
and R/M were significantly lower in K (all over 24 h) and D (for 8 and
4 h, respectively) compared to C. Stress markers were significantly lower
in K and D compared to C at 6 and 24 h, and in K compared to D at
24 h (p < 0.05).
Conclusions: Local wound infiltration with ketamine or
dexmedetomidine added to bupivacaine had an opioid-sparing effect,
delayed first request of rescue analgesia, and attenuated postoperative
stress response, especially with ketamine in patients underwent total
abdominal hysterectomy.